FIXES
screened ships are now given the option to retreat or pass when it is their turn to act in combat
terraforming barren planets now works correctly; colony ships also may now be upgraded in order to get terraforming upgrades
fire button no longer displays at all (fixing the 'null target' bug) when the target is destroyed but the current ship still has shots remaining
Fixed issue with the economy phase builds where the 'counters remaining' section was simply decrementing one per build, effectively blocking large quantity builds in one turn
Minerals and ship wrecks were incorrectly blocking otherwise valid retreat options